卵巢癌（OC）是一种在全球范围内流行的高度侵袭性妇科恶性肿瘤。大多数OC病例通常在晚期诊断，这导致传统治疗后的5年总生存率不到35％。此外，免疫检查点抑制剂疗法在OC患者治疗中显示出有限的疗效，而由于T细胞浸润不足，CAR-T疗法也仅显示出适度的效果。因此，必须开发新的策略来增强T细胞在OC肿瘤微环境中的持久性和迁移能力。 在本研究中，我们基于嵌合抗原受体结构开发了一种新型适应性T细胞治疗卵巢癌的方法。我们使用了一个配体-受体结合基序来增强以CA125为靶点的治疗效果。由于中胚叶细胞黏附素可以与CA125天然结合并具有高亲和力，我们将中胚叶细胞黏附素的核心结合片段与4-1BB和CD3ζ信号片段连接起来，组装成新型CA125靶向嵌合受体（CR）。我们还构建了以4H11抗体为靶点的CAR结构。将编码CR和CAR的RNA电转感染T细胞，评估它们在体外和体内的抗肿瘤活性。 虽然CR-T或CAR-T细胞对两种卵巢癌细胞系表现出中等活性，但共表达CR和CAR的T细胞与仅表达CR或CAR的T细胞相比，具有更强的杀伤效果。此外，在与卵巢肿瘤相互作用时，CR和CAR T细胞释放激活标志物和功能细胞因子的能力显著增加。同样，共表达CR和CAR的T细胞持续控制着移植的卵巢癌肿瘤的生长，并显著延长了受到肿瘤挑战的小鼠的总体生存时间。转录组测序结果显示，相比于仅表达CR或CAR的T细胞，共表达CR和CAR的T细胞的存活能力和细胞毒性明显改变。 我们的研究结果表明，CA125靶向CR和CAR可以协同杀伤卵巢癌细胞，表明在肿瘤中同时靶向这两种结合基序的CA125可能改善卵巢癌治疗的疗效。 © 2023. BioMed Central Ltd., part of Springer Nature.

Ovarian cancer (OC) is a highly aggressive gynecological malignancy prevalent worldwide. Most OC cases are typically diagnosed at advanced stages, which has led to a 5-year overall survival rate of less than 35% following conventional treatment. Furthermore, immune checkpoint inhibitor therapy has shown limited efficacy in the treatment of patients with OC, and CAR-T therapy has also demonstrated modest results owing to inadequate T cell infiltration. Therefore, novel strategies must be developed to enhance T cell persistence and trafficking within the OC tumor microenvironment.In this study, we developed a novel adoptive T-cell therapy for ovarian cancer based on a chimeric antigen receptor structure. We used a ligand-receptor binding motif to enhance the therapeutic effect of targeting CA125. Since mesothelin can naturally bind to CA125 with high affinity, we concatenated the core-binding fragment of mesothelin with the 4-1BB and CD3ζ signal fragments to assemble a novel CA125-targeting chimeric receptor (CR). The CAR structure targeting CA125 derived from the 4H11 antibody was also constructed. CR- and CAR-encoding RNA were electroporated into T cells to evaluate their antitumor activity both in vitro and in vivo.While CR-T or CAR-T cells exhibited moderate activity against two ovarian cancer cell lines, T cells co-expressing CR and CAR exhibited a superior killing effect compared to T cells expressing either CR or CAR alone. Furthermore, upon interaction with ovarian tumors, the ability of CR and CAR T cells to release activation markers and functional cytokines increased significantly. Similarly, CR and CAR co-expressing T cells persistently controlled the growth of transplanted ovarian cancer tumors in NSG mice and significantly prolonged the overall survival of tumor-challenged mice. Transcriptome sequencing revealed that the survival and cytotoxicity of T cells co-expressing CR and CAR were significantly altered compared with those of T cells expressing either CR or CAR.Our findings demonstrate that CA125 targeting CR and CAR can synergistically kill ovarian cancer cells, indicating that CA125 targeting by the two binding motifs simultaneously in tumors may improve the therapeutic outcomes of ovarian cancer treatment.© 2023. BioMed Central Ltd., part of Springer Nature.